1. Rotten wood cannot be carved, nor can a wall of dung earth be made flat. ——From the tenth sentence of Chapter 5 of "The Analects" by Confucius in the Spring and Autumn Period. Translation: Rotten wood cannot be carved, and dung walls cannot be painted.

2. Children cannot be taught. ——Sima Qian of the Western Han Dynasty, "Historical Records: The Liuhou Family". Translation: Children are stupid and cannot draw inferences from one instance to other cases, so trying to reason with them is like playing the piano to others.

3. You will not give up until you reach the Yellow River, and you will not look back until you hit the south wall. ——Anonymous "Collection of Famous Quotes". Translation: It refers to someone who is stubborn in behavior and unable to listen to different opinions.

4. Zhou Lang’s ingenious plan to bring peace to the world cost him his wife and his troops. ——The Romance of the Three Kingdoms by Luo Guanzhong of the Ming Dynasty. Zhou Yu took the initiative to ensure that Sun Quan's sister was married to Liu Bei, and brought Liu Bei to Soochow. He wanted to put him under house arrest to control Shu. However, Zhuge Liang saw through it and sent Zhao Yun to take Liu Bei back. The soldiers Zhou Yu sent to intercept were also defeated by Zhao Yun. . This is the second qi of Zhou Yu's three qi, and now it describes not only failure to accomplish things but also losses.

5. Ning Wuzi, if a country has the Way, it will be wise; if it is without the Way, it will be foolish. It is only within reach, but its stupidity is beyond reach. ——The Analects of Confucius by Confucius in the Spring and Autumn Period. Translation: Ning Wuzi is smart when the country is in peace, but pretends to be stupid when the country is in chaos. His intelligence can be matched, but his stupidity cannot be matched by others.